7. Space / time the following units of measure are used to define storage and transmission capacities

S P A C E					Bits or bytes
Kilo (K) Thousand					1,024
Mega (M) Million					1,048,576
Giga (G) Billion					1,073,741,824
Tera (T) Trillion					1,099,511,627,776
Peta (P) Quadrillion					1,125,899,906,842,624
T I M E					Fraction of second
Millisecond (ms) Thousandth					1/1,000
Microsecond (цs) Millionth					1/1,000,000
Nanosecond (ns) Billionth					1/1,000,000,000
Picosecond (ps) Trillionth					1/1,000,000,000,000
Femtosecond (fs) Quadrillionth					1/100,000,000,000,000
Storage/channel capacity measured in					MEMORY
CPU word size		Bits			Overall capacity		Bytes
Bus size		Bits			SIMM or SIP module		Bytes
Disk, tape		Bytes			Individual chip		Bits
Transmission speed measured in
Network line/ channel	Bits per second			Machine cycle		Microseconds /Nanoseconds
Disk transfer rate	Bits or bytes per second			Transistor switching		Nanoseconds, Picoseconds and Femtoseconds
Disk access time	Milliseconds			Instruction Execution		Microseconds / Nanoseconds
Memory access time			Nanoseconds

I.19 match the words with their definitions.

A An

centimeter kilobyte megahertz nanotechnology gigabyte picosecond femtosecond monorail nanosecond million

is

one thousand bytes. one million cycles per second. a future science that builds devices at the atomic and molecular level. a railway system having one rail. one quadrillionth of a second a unit of measurement that is 1/100th of a meter or approximately 4/10ths of an inch (0.39 inch). one trillionth of a second. one billion bytes. one thousand times one thousand or 10 to the 6th power. one billionth of a second.

i.20 Look through the table 7. space / time given above and make dialogues using the prompts below.

Prompts for Dialogues

• 1. What units is memory access time measured ['meʒəd] in?

• It is measured in nanoseconds.

• What does a nanosecond mean?

• It means ‘one billionth or 10 to the -9th power of a second’.

• What else can be measured in nanoseconds?

• Used to measure the speed of logic and memory chips, a nanosecond can be visualized by converting it to distance. In one nanosecond, electricity travels about six inches in a wire. Even at 186,000 miles per second, electricity is never fast enough for the hardware designer who worries over a few inches of circuit path. The slightest delay is multiplied millions of times, since millions of pulses are sent through a wire in a single second.

• I see.

• 2. How many is ‘mega’ I wonder?

• It means ‘million’.

• What is it abbreviated to?

• "M."

• What is the precise value of ‘mega’ in computer specifications?

• It often refers to the precise value 1,048,576 since computer specifications are usually binary numbers.

• And what does MHz stand for?

• MHz stands for MegaHertZ, megahertz. that is one million cycles per second. It is used to measure the transmission speed of electronic devices, including channels, buses and the computer's internal clock. Megahertz is generally equivalent to one million bits per second or to one million times some number of bits per second.

• MegaHertZ… It’s quite an interesting word. Sounds like German.

• MHz is the heartbeat. When referencing CPU speed, the megahertz rating is really the heartbeat of the computer, providing the raw, steady pulses that energize the circuits. I see you know a little of the German language, so it's easy to remember this. The word "Herz", pronounced "hayrtz," means heart.

• I really appreciate your explanations.